Mitochondrial replacement therapy: the UK and US regulatory landscapes

Abstract

On October 29, 2015, the United Kingdom's regulations on mitochondrial donation (UK 2015 Regulations) came into force.1 This amendment to the UK Human Fertilisation and Embryology Act (the ‘HFE Act’) allows the use of mitochondrial donation techniques as part of in vitro fertilization (IVF) treatments. Mitochondrial replacement therapies (MRT) aim at preventing the transmission of mitochondrial disease from a mother to her genetically related children. In the USA, the use of MRT falls under the oversight of the US Food and Drug Administration (FDA), and its approval, which would require clinical trials under an investigational new drug application, has been currently halted through a rider included in the 2016 Congressional Appropriations Act.2 This note discusses the UK regulatory framework for MRT and compares it to the US landscape. It focuses on the regulatory and ethical discussions in both countries to find some lessons for debates about editing human germ cells.3 The first section introduces some biological characteristics of mitochondria and their implications for mitochondrial diseases, medical interventions and ethical and regulatory questions. The second section discusses the regulatory pathway leading to the adoption of the UK 2015 regulations and the main features of the approved text. The third section considers the current regulatory landscape in the USA. The fourth section discusses some regulatory and bioethical questions raised by MRT.